Advancing mine support locking mechanism - has floor and roof members with locking pegs projecting between links of advancing chains

摘要

The advancing mine support system intended to be adjusted behind a face conveyor has a roof member (4) supported above a floor member (1) by a parallelogram linkage (2) supporting an upper protective shield plate (3). Further forwards is a telescopic cylinder (5) between floor and roof members. A horizontal advancing cylinder (6) is attached at the lower hinge point of the telescopic cylinder. Both floor and roof members carry sets of chains (8, 9) passing completely around them for advancing. The chains are locked by blocking units (13) incorporated in the floor and roof members. These units have pegs which are pushed outwards under spring pressure to fit between the links of the chains to lock them.